[autotest] Only try to symbolicate crash dump when a crashserver is available.

Limit the number of symbolication in crashservers by allocating a crashserver
with enough capacity. If none is found, fail symbolicate_minidump_with_devserver
call with dev_server.DevServerException.

BUG=chromium:489845
TEST=local run
import common
from autotest_lib.client.common_lib.cros import dev_server
print dev_server.get_least_loaded_devserver(devserver_type=dev_server.CrashServer)
http://100.107.160.5:8082

Change-Id: I71e890c8a058c174a11c928f260bb0b0c45df938
Reviewed-on: https://chromium-review.googlesource.com/295168
Tested-by: Dan Shi <dshi@chromium.org>
Reviewed-by: Fang Deng <fdeng@chromium.org>
Commit-Queue: Dan Shi <dshi@chromium.org>
Trybot-Ready: Dan Shi <dshi@chromium.org>
1 file changed